/**
 * Project:   warnme-app
 * File:      PreemptiveAuthenticationRequestInterceptor.java
 * License: 
 *            This file is licensed under GNU General Public License version 3
 *            http://www.gnu.org/licenses/gpl-3.0.txt
 *
 * Copyright: Bartosz Cichecki [ cichecki.bartosz@gmail.com ]
 * Date:      Mar 27, 2014
 */

package dtu.ds.warnme.app.ws.client.https.ssl;

import java.io.IOException;

import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.AuthState;
import org.apache.http.auth.Credentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.impl.auth.BasicScheme;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;

/**
 * @author Bartosz Cichecki
 * 
 */
public class PreemptiveAuthenticationRequestInterceptor implements HttpRequestInterceptor {

	@Override
	public void process(final HttpRequest request, final HttpContext context) throws HttpException, IOException {
		AuthState authState = (AuthState) context.getAttribute(ClientContext.TARGET_AUTH_STATE);
		CredentialsProvider credsProvider = (CredentialsProvider) context.getAttribute(ClientContext.CREDS_PROVIDER);
		HttpHost targetHost = (HttpHost) context.getAttribute(ExecutionContext.HTTP_TARGET_HOST);

		if (authState.getAuthScheme() == null) {
			AuthScope authScope = new AuthScope(targetHost.getHostName(), targetHost.getPort());
			Credentials creds = credsProvider.getCredentials(authScope);
			if (creds != null) {
				authState.setAuthScheme(new BasicScheme());
				authState.setCredentials(creds);
			}
		}
	}

}
